Onset of spin-density-wave antiferromagnetism in Cr/V multilayers

摘要

Spin-density-wave (SDW) magnetism in a series of Cr/V heterostructures with different Cr thicknesses was systematically investigated by combined resistivity, neutron, and synchrotron scattering measurements. We show that the onset of the bulklike SDW state comes through several necessary steps from a paramagnetic state through a commensurate SDW to an incommensurate SDW. The Neel temperature for the incommensurate SDW is found to scale with Cr thickness and reaches the bulk value at a Cr thickness of about 2000 A. The proximity effect from Cr/V interfaces is found to lead to (ⅰ) the appearance of a 50-A magnetically dead Cr layer near Cr/V interfaces and (ⅱ) suppression of the spin-flip transition and stabilization of a single-domain SDW with out-of-plane spins and out-of-plane propagation wave vector. Finally, we show that the SDW period increases with decreasing Cr thickness and becomes temperature independent in sufficiently thin Cr layers.